The other day Ken was trying to tell me that I should sell my nikkor 400mm ƒ2.8 e fl lens and buy the new nikkor 500mm ƒ4 pf instead.
Click on this harrier shot from San Jacinto. Do you see the soft background? That is called bokeh. This shot was taken at ƒ3.2, 1/2500th of a second.
I normally shoot the 400mm at ƒ2.8 to 3.2. You can not get this sort of background separation or speed from an ƒ4.
Never really liked the looks of the pf lenses anyway. They have a strange softness to their output.
If I need greater reach I will either stick the teleconverter on or go to my Sigma 600mm zoom.